二维三轴编织混杂层合复合材料低速冲击性能研究

发布时间：2018-04-25 21:31

本文选题：二维三轴编织混杂层合复合材料 + 低速冲击　；参考：《东华大学》2015年硕士论文

【摘要】：随着复合材料在航空航天等领域的的应用加大，克服单种纤维增强复合材料在冲击性能方面的局限性需求增加，因此混杂复合材料具有广阔的发展前景。目前关于编织混杂层合复合材料低速冲击及冲击后力学性能的研究较少，主要侧重于单层编织复合材料以及单向板层合复合材料的力学性能研究，因此本课题主要对二维三轴编织混杂层合复合材料的冲击性能和冲击后弯曲性能进行实验研究和理论分析，以期能为编织混杂层合复合材料的抗冲击应用设计提供参考。本文以两大类共七种结构类型试样为研究对象，第一类结构类型包含四种层合结构，分别为：3层碳纤编织片层合制得；上下两层为碳纤编织片、中间层为玻纤编织片层合制得；上下两层为玻纤编织片、中间层为碳纤编织片层合制得；3层玻纤编织片层合制得。第二类结构类型包含三种层合结构，分别为：3层均由碳纤为编织纱、玻纤为轴纱的编织片层合制得；3层均由玻纤为编织纱、碳纤为轴纱的编织片层合制得；3层均由编织纱和轴纱是碳纤和玻纤一隔一混杂排列的编织片层合制得。本课题采用落锤冲击实验和三点弯曲实验进行力学性能综合测试，利用数码相机观察表面损伤分布、体式显微镜观察横截面和纵截面的断面损伤特征。通过冲击实验所得损伤规律和数据对比初步判断材料的抗冲击性能，由不经过冲击的纯弯曲实验推出试样的弯曲性能，进而与冲击后的弯曲性能进行对比，分析得出剩余弯曲性能较好的复合材料试样，从而得出具有较优抗冲击性能的复合材料试样。上下两层为碳纤编织片、中间层为玻纤编织片制得的层合复合材料与3层均为碳纤编织片制得的层合复合材料相比，前者的冲击表面裂纹较少、冲击中心处横截面裂纹较少，而单位厚度吸收能量比后者高7.61%、最大弯曲载荷值比后者高16.46%、弯曲强度高19.52%、冲击后弯曲强度损失率低40.60%，因此可得出3层编织层合复合材料的外层为刚性材料编织片、中间层为韧性材料编织片时，可有效提高混杂材料的抗冲击性能。上下两层为玻纤编织片、中间层为碳纤编织片制得的层合复合材料与3层均为玻纤编织片制得的层合复合材料相比，前者的冲击表面裂纹较少、冲击中心处横截面裂纹较少，而单位厚度吸收能量比后者高2.21%，最大弯曲载荷值比后者高2.12%、弯曲强度高11.46%、但是冲击后弯曲强度损失率仅高5.30%，因此可得出外层为韧性材料编织片、中间层为刚性材料编织片时，可在较小程度提高混杂材料的抗冲击性能。 3层均由碳纤为编织纱、玻纤为轴纱的编织片层合制得的混杂复合材料，与3层均由玻纤为编织纱、碳纤为轴纱的编织片层合制得混杂复合材料相比，前者的冲击正面裂纹较多、冲击背面裂纹较少、冲击中心处横截面裂纹较多，单位厚度吸收能量比后者高25.80%，最大弯曲载荷值比后者高18.64%、弯曲强度高15.25%、但是冲击后弯曲强度损失率高98.83%；而3层均由编织纱和轴纱是碳纤和玻纤一隔一混杂排列的编织片层合制得的混杂复合材料，冲击表面和冲击中心处横截面裂纹损伤范围较小，但单位厚度吸收能量最大、最大弯曲载荷值最高、弯曲强度值最低、冲击后弯曲强度损失率接近最低，由此可知，编织片为韧性材料和刚性材料混杂编织制得时，，抗冲击性能会下降，但编织纱为韧性材料、轴纱为刚性材料的整体性能较好。 3层编织层合复合材料的外层为刚性材料编织片、中间层为韧性材料编织片时，可有效提高材料的抗冲击性能；外层为韧性材料编织片、中间层为刚性材料编织片时，可在较小程度提高材料的抗冲击性能；而编织片为韧性材料和刚性材料混杂编织制得时，抗冲击性能会下降，而编织纱为韧性材料、轴纱为刚性材料时整体性能较好。
[Abstract]:With the increasing application of composites in aerospace and other fields, the limited demand for impact properties of single fiber reinforced composites is increased. Therefore, hybrid composites have broad prospects for development. At present, there are few studies on the mechanical properties of braided hybrid composites at low velocity impact and impact. The mechanical properties of single layer braided composites and unidirectional laminates are studied. Therefore, the research and theoretical analysis of the impact and post impact bending properties of the two dimensional three axis braided hybrid composites are conducted in order to provide a reference for the impact application design of the woven hybrid laminated composites. Exam.
In this paper, two types of seven kinds of structural types are taken as the research object. The first type of structure type contains four layers of laminated structure, which are composed of 3 layers of carbon fiber braided sheets, the upper and lower two layers are carbon fiber braided pieces, the middle layer is made of glass fiber braided laminates, the upper and lower two layers are glass fiber braided pieces, and the middle layer is made of carbon fiber braided sheets. The 3 layers of glass fiber braid are made up. The second types of structural types include three kinds of laminated structures, respectively: the 3 layers are made of carbon fiber woven yarn and glass fiber for axial yarn. The 3 layers are made of glass fiber as braided yarn and carbon fiber as shaft yarn, and the 3 layers are all arranged in a mixed arrangement of woven and glass fiber. The weave sheet is laminated.
This subject uses the drop hammer impact test and the three point bending test to carry out the comprehensive test of the mechanical properties. The damage characteristics of the cross section and the longitudinal section are observed by the digital camera. The damage characteristics of the cross section and the longitudinal section are observed by the body microscope. The impact resistance of the material is preliminarily judged by the damage law and the data comparison obtained by the impact test, and the impact is not impacted by the impact test. The bending properties of the specimen are introduced by the pure bending test, and then compared with the bending properties after the impact, the composite materials with better residual bending properties are analyzed and the composite materials with better impact resistance are obtained.
The upper and lower two layers are carbon fiber braided pieces, and the interlaminating composite material made by glass fiber braided interlayer and the 3 layer are both carbon fiber woven laminated composites. The former has less impact surface crack and less crack in the cross section of the impact center, while the unit thickness absorption energy is 7.61% higher than the latter, and the maximum bending load is 16. higher than the latter. 46%, the bending strength is 19.52%, and the loss rate of bending strength is low after impact of 40.60%. Therefore, it can be concluded that the outer layer of the 3 layer woven laminated composites is a rigid material braided piece, and the middle layer is made of ductile material, which can effectively improve the impact resistance of the hybrid material.
The upper and lower two layers are glass fiber braided pieces, and the interlaminating composite material made in the middle layer is made by carbon fiber braided pieces and the 3 layers are all laminated composites made of glass fiber braided sheets. The former has less impact surface cracks and fewer cracks in the cross section of the impact center, while the absorption energy per unit thickness is 2.21% higher than that of the latter, and the maximum bending load is 2.1 higher than the latter. 2%, the bending strength is 11.46%, but the loss rate of the bending strength is only 5.30% high after the impact. Therefore, it can be found that the outer layer is a ductile material braiding piece and the middle layer is a rigid material. The impact resistance of the hybrid material can be improved to a lesser extent.
The 3 layer is a hybrid composite made of braided yarn and glass fiber as a weave yarn. Compared with the 3 layers, which are woven with glass fiber as braided yarn and the carbon fiber as the axial yarn, there are more cracks in the front face, less cracks on the back of the impact, more cracks in the cross section at the impact center and the suction unit thickness. The maximum bending load is 25.80% higher than the latter, the maximum bending load is 18.64% higher than the latter, and the flexural strength is 15.25%, but the loss rate of the bending strength is 98.83% after the impact. The 3 layer is a hybrid composite of braided yarn and shaft yarn arranged in a mixed arrangement of carbon fiber and glass fiber, and the cross section crack at the impact surface and the impact center. The damage range is small, but the unit thickness absorbs the maximum energy, the maximum bending load is the highest, the bending strength is the lowest, and the loss rate of bending strength is close to the lowest. Therefore, when the braided piece is made of ductile material and rigid material, the impact resistance will fall down, but the woven yarn is ductile and the axle yarn is rigid. The overall performance is good.
The outer layer of the 3 layer woven laminated composite material is a rigid material braiding piece and the middle layer is made of ductile material. It can effectively improve the impact resistance of the material. The outer layer is a ductile material braided piece and the middle layer is a rigid material. The impact resistance of the material can be improved in a small degree, while the braided sheet is a ductile material and a rigid material. When the material is mixed and woven, the impact resistance will decrease, while the braided yarns are tough materials, and the overall performance is better when the yarns are rigid materials.

【学位授予单位】：东华大学
【学位级别】：硕士
【学位授予年份】：2015
【分类号】：TB332

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